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Police stressed there was no threat to the community, with the arrest unrelated to any previous investigation carried out by counter-terrorism teams.

A handful of terror-related attacks have been foiled on home soil over the past 18 months, authorities have said, but several have taken place, including the murder of a Sydney police employee in October.

Counter-terror police have made a series of arrests since late 2014, including a 16-year-old boy charged with preparing an attack linked to Anzac Day services honouring Australian soldiers in Sydney in April.

Other arrests saw a 17-year-old boy picked up in a raid in Melbourne a year ago, allegedly with "improvised explosive devices" in his family home.

More recently, a Sydney-based man was charged last month with planning a terrorist attack, which reportedly involved targeting a naval base close to the capital's landmark opera house.

The government has become increasingly concerned about homegrown extremism and the terror threat level was raised to high in September 2014.

Australia is also worried about its citizens fighting with jihadist organisations such as Islamic State in Iraq and Syria, with some 110 citizens already having left to join such groups.